@LarryE
Hey Larry. I'm using AutomationDirect's PLC P2-550 which is part of the same family line and uses tags as well. I setup a demo of Mango and was able to read/write values without an issue. I didn't use the AB data source, instead I just enabled modbus on my controller and created modbus addresses for any tag I wanted to read. Not quite as easy/clean as being able to reference the tag name directly but it works great.
Best of luck!
Adam